Total power and specific heat

If the total power per unit area from the Sun incident on a horizontal leaf is 9.00x10^2 W/m2, and we assume that 70.0% of this energy goes into heating the leaf, what would be the rate of temperature rise of the leaf? The specific heat of the leaf is 2.80 kJ/(kg°C), the leaf area is 7.00 x10^−3 m2, and its mass is 0.200 g.